Grooving tool



like.

Patented Sept. 2S, i923.

earsnr tries.

JON F. MORGAL, OF SPRINGFIELD, CHIC2 ASSIGNOR, BY MESNE ASSGNMENTS, T0 BERNARD E. CRABBS.

GRoovING Toor..

,Application ledfOct-ober 6, 1921.` Serial No. 505,750.

rlhis invention relates to grooving tools and is designed more particularly for iinishing the sides of piston rings grooves and the The ring groove of a piston must have its sides parallel and must becut in a very exact position with relation to the cylindrical surface of the cylinder. Consequently, the facing, or nishing, of the side walls of the groove is a difficult Aoperation and as ordinarilyy performed requires hiohly skilled labor. Vhen it is desired to renew the piston rings in a piston, itis frequently found that the old rings have battered the walls of the grooves so as to distort the same'by forming shoulders therein which prevent the new rings from fitting properly, so that very frequently Vthere is worse leakage about the rings after new rings have been inserted than there was with the old rings. New piston rings are usually inserted at commercial garages and such garages are not equipped either with the machinery or the character of labor necessary to refinish the sides of the groove so that they will properly fit a new ring. Y Y y One object of the present invention is to provide a grooving tool which can be easily operated by unskilled labor to finish the sides of a groove accurately and maintain the same in proper relation to the surface of the piston.

A further object ofthe invention is to provide such a tool which will be so constructed Yet() that it can not be improperly operated, thus making it practically fool proof and insuring a proper finishing of the grooves in the hands of unskilled labor.

f A. further object of the invention is to provide such a tool which will be very simple in its construction and of a strong, durable character. L

Gther objects of the invention will appearas the device is described in detail.

ln theaccompanying drawings Fig. l is a plan view, partly broken away, of a grooving tool embodying my invention and showing the same applied to a piston; Fig. 2 is an Venlarged sectional view taken on the line 2 2 of Fig. l; Fig. 3 is an enlarged sectional view taken on the line 3 3 of Fig. l; Fig. l is a section taken-on the line 4-4of Fig. l; Fig. 5 is a section taken on the line 5,-5 of Fig. l; Fig. 6 is a section taken on the line 6--6 of Fig. l; and Fig. 7 isa section taken on the line 7 7 of Fig. l.

In these drawings I have illustrated one embodiment of my invention and have shown the same as comprising a supporting structure or body adapted to extend about a piston, or other cylindrical structure having a circumferential groove in the external wall thereof. yThis st-ructure carries a cutter adapted to enter the groove and the position of the critter in the groove is controlled by guides which extend into the groove, preferably to a point near the base thereof sothat the cutter is maintained at all times in proper relation to the side walls of the groove-and,l

consequently, as the supporting structure is rotated about'the piston the cutter will cutl ther understood that the particular embodiy ment of the invention here` illustrated has been chosen for the purposes of illustration only and that the invention may take various forms without departing from the spirit thereof.v

In that embodiment of the invention here illustrated the supporting structure, or body,

`'is in the form ofan annulus which extends entirely about the piston, the central opening in the structure being of sufficient diameter to permit the piston to be inserted therein. If desired for convenience of manufacture the annular supporting structure may be formed in two parts, a main lower portion l and an upper portion, or cap ring, 2, which is rigidly secured to the lower portion. The 1 structure is provided with suitable meansfor rotating it and as the present tool is designed primarily for operation by hand I have formed integral with the main portion l thereof a handle 3. A cutter is mounted on the supporting structure and may be prov jected beyond the inner wall thereof so that it may enter the piston ring groove. This lcutter may be of any suitable form, but in the present instance it is shown at fl as a bar Cil oti tool steel having its inner end provided with cutting edges. rIhe cutter is adjustable to enable it to be advanced into the groove as the work progresses and to that end I have slidably mounted it in a sideway, or channel 5 extending transversely to the body portion l of the supporting structure and lengthwise of the handle 3. The outer end of the cutter has a reduced extension which is screw threaded. as shown at G and a milled nut 7 is screw threaded onto this reduced portion and is rotatably mounted in a recess 8 in the handle. thus permitting the cutter' to be adjusted by the thumb and linger ol the hand which rotates the tool a whole.

In order that the cutter may be maintained in proper relation to the piston ring groove at all times during the linishing operation I have provided the supporting structure with a plurality of guides which. in the present instance, are shown as rollers 9 mounted in recesses l0 in the supporting structure and rotating about axes parallel with the axis about which the lool as a whole rotates. These rollers project beyond the inner wall ot the supporting structure and ee:- tend into the piston ringl grooves tor substantially the full depth thereof, that is, they either contact with or are arranged close to the base of the groove. rI-he rollers are ol" a thickness approximately equal to the width of the original groove so that they will engage the side walls ot the groove and hold the tool as a whole against movement transversely ot the groove, but will permit the same to rotate about the piston, thereby guiding the cutter with relation to the groove. In the case ot an old piston the grooves will, as has been explained, ett-en be found to have shoulders termed therein by the action of the old rings, these shoulders being shown in exaggerated form at l1. Figs. 2 and 3,the piston as a whole beingr indicated by the reference numeral l2. It will be noted that the shoulders are spaced some distance :trom the base of the groove and that, therefore, the inner portion of the groove conforms to its original size and position and the rollers extending into this inner portion ot the groove cause the groove to be positioned. when reiinished, in exactly the same relation to the piston as was the original groove. rI'he cutter 4 preferably extends above and below the planes ot the upper and lower surfaces ot the rollers, respectively, so that it will simultaneously cut both the upper and lower sides of the groove.. Consequently, the side walls ot the groove are absolutely. parallel and because of the action of the guides each side ot the groove will lie in exactly the same plane throughout the circumference ot the groove, and. further, the tool being held against any tilting movement the groove will be at right angles to the axis of the piston. In order. that the tool may be placed on and removed trom the piston the guide rollers are removably mounted in the recesses` l0. As here shown, the recesses are lormed wholly in the lower, or body, portion of the supporting structure and the upper sides are closed b y the upper portion, or cap ring.l 2 which is rigidly secured to the lower portion by screws 13, there being preferably one ot these screws on each side ot each roller. The rollers are secured in position within the recesses by means of removable pins llwhich extend through both parts ot the supporting structure and through the roller, these pins being preferably provided with heads l5 to Vtacilitate their removal. It will be apparent that b v removing the pins the rollers may be slipped outwardly, the structure placed about a piston, and the rollers then inserted in the groove and the pins replaced. It will be understood, ot course, that the cutter. is retracted until a'tter the tool has been placed in position and then adjusted to bring the cuttinget ges thereu'l in contact with the walls of the groove. Alfter the groove has been completely rctinished the pins are again withdrawn and the rollers removed to permit the tool either to be shitted to a new groove in the same piston or to be removed 'from the piston. To -facilitate the withdrawal et the rollers .trom the grooves the lower and upper members ot this structure are provided in their outer edges. adjacent to the recesses 10, with recesses 1G and 1T which enable the rollers to be grasped between the lingers and drawn outwardly. I have also shown the structure as a whole as provided in its inner edge with a recess 1S which extends to a point below the level ol the groove and enables the operator to inspect the groove from time to time to note progress ot the work.

The supporting structure ot the tool may. it desired. tit closely about the piston to which it is applied but this is not necessary and it is wholly practical to utilize one tool for several pistons ot dit'ferent diameters. it being only necessary to provide a dillerent set of guide rollers tor each size ol piston. The guide rollers being mounted on fixed axes will. it ot the proper diameter. support the tool in proper relation to the piston regardless ot whether or not the supporting structure itself comes in contact with the piston.

The operation ot the device will be readily understood from the toregoingdescription and it will be apparent that the construction of the device is such that it can be applied to the piston in one way only and that after it is applied to the piston its operation is antomatically controlled so that the retinishing ot the groove is necessarily properly accomplished, thus` enabling eilicient worl; to be accomplished by an unskilled workman.

lill) lbf) lili

vFurther, it vvill be apparent that the tool renders unnecessary the placing of thepislton in a lathe and accurately centering the same, as must be `done When the rings are rigid character andninay be k'easily sharpened or replaced. v n

While I have shown and described one embodiment of my invention I Wishit to be understood that I do not desire to be limited to the details thereof as various modifications may occur to a person slrilled in the art.

Having noW fully described my invention vvhat I'claim as new and desire to secure by Letters Patent, is I f l. lIn a tool of the character described, 'a supporting structure adaptedf to extend about the exterior of a cylindricaly body having a circumferentialgroove, the outer porT tion offivhich has been distorted, a cutter carried by said structure vand varranged to enter said groove, and a plurality of guides carried by said'structure, arranged to travel in the inner undistorted portionV of said groove andso spaced With relation'to said Structure that they will support said struc-` ture andsaid cutter in the plane of said groove. Y i 'n 2. In a tool of the character described, a supporting structure adapted to extend about the exterior of a cylindrical body and having a circumferential groove, the outer portion of Which has been distorted, a cutter carried vby said structure and arranged to enter saidy groove, anl'guides carried by said structure and arranged to travel in saidl groove in contact with both side Walls of the inner undistorted portion thereof and to therebycause said cutter to travel in the plane of said groove. y

3. In a tool of the character described, a one-piece annular structure adapted to be placed about a cylindrical body having a circuniferential groove, the outer portion of Which has been distorted, a cutter carried by said structure and arranged to enter said groove', and guide rollers mounted on said structure in fixed alinement one With the other and arranged to travel in the inner undistorted portion of said groove and to thereby support said structure inthe plane of said grooves.

a. In a tool of the character described, a supporting structure adapted to extend about' a cylindrical body having a circumferential groove the outer portion of which has been distorted, means for rotating said structure about said body, a cutter carried by said structure and arranged to enter said groove, means for adjusting said cutter radially to said structure, and guide rollers carried by saidstructure and arranged to travel in said groove in contact with both side' Walls of the inner undistorted portion thereof and to thereby cause said cutter to travelr in a plane perpendicular 'to the axis of said cylindrical body;

5. In a tool ofthe character described, a supporting structure adapted to extend about a cylindrical body and havinga circumferential groove `the outer portion of- Whicli has been distorted, a cutter carried by said structure andarranged to enter said` groove, said cutterhaving cutting edoes to act simultaneously on both sides or said groove, and guides carried by said structure and arranged to travel in said groove in contact With both side Walls of the inner lundistorted portion thereof and to cause said cutter to travel in a plane perpendicular to the axis of said cylindrical body.

6. Ina tool of the character described, a supporting structure adapted to extend ,about a cylindrical body having a circumferential groove, a cutter carried by said structure and arranged to enter said groove,A

guides carried bysaid structure and arranged to travel in said groove and support said cutter in operative engagement With both Walls thereof, and maintain the same in the plane lof said groove, means for rotating said 'structure labout said 'cylindrical body, and means for advancingV said' cutter into said groove after each rotation of the supporting structure. Y 7 In a tool of the character described, a one piece annular structure adapted to eX- tend entirely about a cylindrical body having a circumferential groove, a cutter car'- ried by said structure and adapted to operatively engage the Walls of said groove, guides carried by said structure and arranged to travel in said groove and to support said cutter in a plane perpendicular to the axis of said cylindrical body, said guides being movably mounted on said annular structure to permit them to be inserted in or Withdrawn from said groove When said annular structure is in position on said cylindrical body, and means for rotating said structure about said cylindrical body.

8. In a tool of the character described, an annular supporting structure adapted to extend entirely about the exterior of a cylindrical body having a circumferential groove, a cutter carried by said structure and adapted to extend into said groove and to simultaneously act upon both Walls of said groove, a plurality of rollers mounted on said structure and adapted to extend into said groove for substantially thefull depth thereof to control the position of said cuter With relation thereto, said rollers being capable oi' bodily movement relative to said structure to permit said structure to be placed about said cylindrical body, and means for rotating said structure around said cylindrical body.

9. In a tool of the character described, an annular` supporting structure adapted to -extend entirely about a cylindrical body having a circumferential groove, a cutter adjustably mounted on said structure and arranged to be moved into and out ot said groove, said critter having cutting edges to engage both ot the Walls of said groove, recesses formed in said supporting structure, rollers mounted in said recesses and extending beyond the wall of said structure into said groove, and means to rotate said strueture.

10. In a tool of the character described, an annular supporting structure adapted to extend about a cylindrical body having a circumferential groove, a critter carried by said structure and arranged to enter said groove, said structure having a plurality ol reciV therein, a roller mounted in each oi' said recesses and projecting beyond the inner wall ot said structure, each roller being ot such a diameter that it vvill extend into said groove for substantially the full depth thereot, and means for rotating said structure.

l1. In a tool oli' the character described` a supporting structure adapted to extend about a cylindrical body having a circumferential groove, said structure having` a plurality of recesses therein, a cutter mounted on said structure and arranged to enter said groove, rollers mounted in the respective recesses, and arranged to travel in said groove,

said rollers in means for removably securing rotating said critter into and out of said groove. rollers mounted in the respective recesses in said structure and arranged to travel in said groove to control the position ol' said cutter with relation to the Walls of said groove, and means for removably securingl said rollers in said recesses.

13. In a tool ot the character described, an annular supporting structure adapted to extend about a cylindrical body having a circumferential groove, said structure having recesses opening through the inner vvall thereof between its upper and loiver edges, rollers, mounted in said recesses and arranged to travel in said groove, a cutter carried hv said structure and arr ged to enter said groove, and means for rotatae said annular' structure, said annular structure having a recess'in the inner wall thereof extending liioni the upper surface ol said structure to a point below said groove, whereby the progress of the vvorl; may he inspected.

In testimony whereof, l aiix my signature hereto.

JOHN F. MORGLL. 

